Tamoxifen(TAM)is an important therapeutic strategy for the treatment of estrogen receptor(ER)-positive breast cancer.However,tamoxifen resistance is a major cause of endocrine therapy failure.The potential mechanism of TAM resistance is multifactorial and most of them are still unknown.This review presents recent advances in the mechanism of TAM resistance in breast cancer,providing valuable information and ideas for elucidating the mechanism of tamoxifen resistance and overcoming drug resistance.

Adult ; Anti-Bacterial Agents ; adverse effects ; Female ; Humans ; Laryngeal Diseases ; etiology ; microbiology ; Mycosis Fungoides ; etiology ; Prescription Drug Misuse ; Substance-Related Disorders ; complications ; Young Adult

Objective To investigate the effect of insulin-like growth factor-1(IGF-1) and basic fibroblast growth factor (bFGF) on the differentiation of human dental pulp stem cells in vitro. Methods Mono-cell suspension was separated from the human adult dental pulp with collagenase Ⅰ and dispase digestion. Colony-forming efficiency of cells was calculated. Cells were observed under an invert microscope. Dentin sialoprotein (DSP), dentin matrix protein 1 (DMP-1) and dentin sialophosphoprotein (DSPP) mRNA of the 3rd passage cells induced with IGF-1 and bFGF in vitro were detected by immunohistochemistry and RT-PCR. Results Clonogenic cells were obtained from dental pulp and colony-forming efficiency of cells was 2.6-3.5 colonies/10 4 cells. Human specific DSP, DMP-1 protein and DSPP mRNA expressed in colony-forming cells after 7 d of induction with IGF-1 and bFGF in vitro. Conclusion Adult stem cells might exist in human dental pulp. Dental pulp stem cells could differentiate into odontoblast under the induction of IGF-1 and bFGF.

Objective To investigate the protective role of dexmedetomidine in rats with endotoxin-induced acute lung injury (ALI).Methods Forty-eight adult male SD rats were divided into four groups (n=12 each) according to the random number table: control group, lipopolysaccharide (LPS) group, dexmedetomidine (DEX) treatment group and DEX pretreatment group.ALI was induced in rats by femoral intravenous injection of LPS (8 mg/kg).Rats in DEX treatment group was given DEX (50 μg/kg) for 2 minutes via the femoral intravenous injection 0.5 hour after LPS injection, followed by maintenance pump injection of DEX (5 μg·kg-1·h-1).Analogously, rats in DEX pretreatment group was given DEX (50 μg/kg) for 2 min via the femoral intravenous injection 0.5 hour before LPS injection, followed by maintenance pump injection of DEX (5 μg·kg-1·h-1).By contrast, control group received the same amount of normal saline intravenously.All rats were sentenced to death and their carotid blood samples were collected6 hours after all injections.Superior lobe of the right lung was examined under light microscope and the histologic findings were tested using the difusse alveolar damage (DAD) score.Middle lobe of the right lung was used to calculate the lung tissue wet/dry weight (W/D) ratio.Samples of collected carotid blood were taken to measure levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6.Bronchoalveolar lavage fluid (BALF) obtained from bronchoalveolar lavage was collected to measure levels of TNF-α and IL-6.Results Lung tissue injury was obvious after LPS injection and DAS score was improved as well.However DEX therapy reduced the lung damage as well as the DAD score, especially obvious in DEX pretreatment group (P<0.05).W/D ratio was obviously increased in other three groups compared to control group, but further comparison showed that W/D ratio was lowered in DEX treatment and pretreatment groups compared to LPS group, especially obvious in DEX pretreatment group (P<0.05).Levels of TNF-α and IL-6 were higher in other three groups than control group, but further comparison showed that levels of TNF-α and IL-6 were decreased in DEX treatment and pretreatment groups compared to LPS group, especially obvious in DEX pretreatment group (P<0.05).Levels of TNF-α and IL-6 in BALF were higher in LPS and DEX treatment groups than control group and were higher in LPS group than DEX treatment(P<0.05).Further comparison showed level of TNF-α in BALF similar between DEX treatment and pretreatment groups (P>0.05), but IL-6 in BALF was significantly lower in DEX pretreatment group than DEX treatment group (P<0.05).Level of total protein in BALF was increased in LPS group compared to control group and was decreased in DEX treatment and pretreatment groups compared to LPS group, but there were no significant differences between DEX treatment and pretreatment groups (P>0.05).Conclusion Either preoperative injection of DEX or DEX treatment has protective effect in rats with LPS-induced ALI, while preoperative injection of DEX has been proved to be more effective.

Objective: To analyze the relationship between hemoglobin ( Hb ) and serum uric acid ( SUA ), so as to provide basis for preventing hyperuricemia ( HUA ) . Methods: As the research subjects, people who underwent physical examination in Zhejiang Provincial People's Hospital from January 1, 2017 to October 31, 2020 for 4 years in a row and who were non-HUA in 2017 were selected. The physical examination data were collected, including body mass index, blood pressure, blood routine, blood biochemical tests, etc. The subjects grouped by quartiles of Hb level in 2017. The occurrence of SUA elevation ( SUA increased ≥60 μmol/L from baseline ) , significantly SUA elevation ( SUA increased ≥120 μmol/L from baseline ), HUA ( SUA>420 μmol/L ) and severe HUA ( SUA ≥480 μmol/L ) in the next 3 years were taken as end events. The incidence, occurrence time and risk of end events in different Hb groups were analyzed. Results: A total of 4 073 subjects were selected and divided into 4 groups according to the Hb level from low to high, with 969 subjects in group A, 907 subjects in group B, 1 109 subjects in group C and 1 088 subjects in group D. SUA elevation was in 745 patients ( 18.29% ); significantly SUA elevation was in 105 patients ( 2.58% ); HUA was in 514 patients ( 12.62% ); severe HUA was in 94 patients ( 2.31% ). The incidence of SUA elevation and significantly SUA elevation showed a decreasing trend with the increase of Hb level ( P<0.05 ). The occurrence time of SUA elevation in group A to D was 2.788, 2.817, 2.860 and 2.814 years, and the difference was statistically significant ( P<0.05 ). There were no statistically significant differences in the occurrence time of other end events ( P>0.05 ). The multivariate Cox proportional hazards regression analysis showed that compared with group A, other Hb groups had lower risk ( HR=0.498-0.776, 95%CI:0.253-0.981 ) of SUA elevation, significantly SUA elevation and severe HUA after adjusting for gender, age, ALT, Scr, body mass index, etc. Conclusions With the increase of Hb level, the incidence of SUA elevation may decrease and the occurrence time is prolonged. Compared with the lowest Hb group, the higher Hb groups had lower risk of SUA elevation, significantly SUA elevation and severe HUA.

Aim To establish a mouse breast cancer model stab-ly expressing HER2. Methods 4T1-Luc mouse breast cancer cell line was transfected with the full-length human HER2 gene and selected with G418. The HER2 expression in 4T1-Luc stable cells was detected by fluorescence-activated cell sorting ( FACS) and Western blot. 4T1-Luc/HER2 cells were implanted into the mammary fat pads of BALB/c or nude mice. After tumor stabili-zation, mice were randomly assigned into 4 groups for treatment with PBS control, chA21, Trastuzumab, or chA21 plus Trastu-zumab. Tumor volumes were measured and tumor growth inhibi-tion ratios were calculated twice a week. At the end of experi-ment, tumor metastasis in mice was detected by bioluminescence imaging technology. Results Several 4T1-Luc/HER2 stable cell clones were obtained after G418 selection. FACS and West-ern blot analysis showed that all clones expressed HER2 protein at high levels. These 4T1-Luc/HER2 clones showed good tumor-igenicity in mice with steady tumor growth after one week of cell implantation. After 2-3 weeks, metastatic tumor cells were seen in the lung, cheek and groin areas. In BALB/c mice, the tumor growth inhibition ratio was 43. 3% in chA21 plus Trastuzumab group (P<0. 05 vs PBS control), which was higher than chA21 group (11. 1%) or Trastuzumab group (23%). In addition, the luminescence number and density of tumor metastases in lungs were significantly reduced in the antibody combination group. Conclusions The mouse model of spontaneously metastasizing breast cancer with HER2 overexpression is successfully estab-lished. The preliminary study suggests that anti-HER2 antibody combination of chA21 and Trastuzumab has excellent inhibitory effects on tumor growth and metastasis.

Objective To analyze the popular characteristic and drug resistance of Pseudomonas aeruginosa in a hospital of Guiy-ang from January 201 1 to December 2013.Methods The distribution characteristic and drug resistance of Pseudomonas aeruginosa isolated from clinical samples from January 201 1 to December 2013 were analyzed retrospectively.Results A total of 642 strains of Pseudomonas aeruginosa were isolated for three years in our hospital from January 201 1 to December 2013,there was 57.0% isola-ted from sputum specimens,and 27.9% isolated from excreta of wound.The infected endemic area distribution was made up of Or-thopedic Surgery,ICU,Geriatrics Department and Respiratory Department accounting for 22.9%,20.1%,18.8% and 1 5.9% re-spectively.Pseudomonas aeruginosa was most sensitive to polymyxin bacillosporin.The drug resistance rates to Trimethoprim,Am-picillin and Cefazolin were all 100.0%.The drug resistance rates to Ampicillin/sulbactam and Ceftriaxone were 90.0%. Conclusion Pseudomonas aeruginosa is the main cause of lower respiratory tract infections in patients and wound infection and show serious multi-drug resistant,so it is necessary to use drugs reasonably according to the drug susceptibility results.

OBJECTIVE: To investigate the distribution of multiple food allergens in patients with allergic rhinitis in Guangzhou area. METHOD: Skin prick tests were performed in 1529 patients with allergic rhinitis. The result was discussed by the age of patients, the types of allergens and the response intensity. RESULT: Five hundred and eighty-seven cases were positive. The most important food allergens were crab (25.6%), prawn (19.4%). There were statistical differences of positive reactions among three age groups (P < 0. 05). The main food allergen was seafood. CONCLUSION Crab and prawn are the main food allergens in patients with allergic rhinitis in Guangzhou. It is helpful for clinical diagnosis and treatment.
Adolescent ; Adult ; Aged ; Allergens ; analysis ; Animals ; Child ; Child, Preschool ; China ; epidemiology ; Dairy Products ; Eggs ; Female ; Food ; Food Hypersensitivity ; epidemiology ; Humans ; Male ; Meat Products ; Middle Aged ; Rhinitis, Allergic ; Rhinitis, Allergic, Perennial ; epidemiology ; Seafood ; Skin Tests ; Young Adult

Objective:To investigate the expression and regulation of the platelet-activating factor receptor(PAF-R)in human keratinocytes.Methods:The expression of PAF-R in skin tissues and HaCaT cells was examined by immunohis-tochemistry.The expression of PAF-R in HaCaT cell mRNA level was detected by RT-PCR.The expression and regulation of PAF-R were measured by flow cytometry in HaCaT cells treated with various stimuli.Results:The expression level of PAF- R was very high in human keratinocytes,mainly located on cell membranes and cytoplasma.PAF-R also expressed on HaCaT cells transcription levels,and the tissue-type PAF-R mRNA was more than that of leucocyte-type PAF-R mRNA.PAF-R ex-pressed on both membrane and intracellar part of HaCaT cell,and the intracellular expression was about4.82times that of membrane expression.IFN-?and retinoic acid upregulated the membrane expression of PAF-R in HaCaT cell.Conclusion:Human keratinocytes can highly express PAF-R at cell,protein and transcription levels,and the expression characteristic can be regulated by some inflammatory factors,which indicates the PAF system may play an important role in the skin inflamma-tion. [

OBJECTIVE:To study the effect of the hematostatic effective components of Herba Lamiophlomis rotata on rat’s blood conglomeration parameters.The toxicity of these components was simultaneously studied.METHODS:Herba Lamiophlomis rotata water extract (HLRE)(3g?kg-1),Total Flavonoids(P1,0.36g?kg-1),Total Iridoid Glycosides(P2,0.99g ?kg-1),Maximus Polarity Components(P3,1.65g?kg-1)and normal sodium NS were given orally in rats for 14 days.Blood samples were collected from common carotid artery;prothrombin time (PT),activated partial thromboplastin time (APTT),thrombin time (TT)and fibrinogen (FIB)were tested.Different oral doses of(P2 ,1.4,0.7,0.35 g?kg-1)and Yunnan white powder (BY,0.9g?kg-1)were given to rats and conglomeration parameters were determined too.The maximum tolerable dose (MTD)and LD50 of mice were determined after different doses of P2 were given with oral administration and intraperitoneal injection.RESULTS:Compared to NS control group,each composition of Lamiophlomis rotata Kudo can shorten the TT by 18.59%、—3.12%、24.11%and 9.92%respectively,and increase the content of FIB by 25.32%、8.67%、28.29%and 5.36%respectively.There was obvious change in HLRE and P2(P